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Complex number problem

  1. May 30, 2005 #1
    Someone solve this please!!!!!

    If z= CosA+iSinA, express 2/1+z in the form I-Tan(kA).
  2. jcsd
  3. May 30, 2005 #2


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    Well,what is that number (2/(1+z)) equal to?

    And what do you mean by "I-Tan(kA)"...?

  4. May 30, 2005 #3
    where k is a constant and A is the angle from above, it says to express the answer in that form- z is a complex number in polar form.
    I tried multiplying the 2/(1+z) by the conjugate (1-z) on the top and bottom but I can't get it into the form 1-Tan(kA).
    I think this involves trignometric identities and de Moivre's theorem.
  5. Jun 1, 2005 #4
    you write z as (cosA + i SinA) and multilply the denominator by (1+ CosA --iSinA)...Simplify it...
    Answer will come
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